Filtration & separation machinery

Dewatering: mother liquor is separated from the solid phase of the slurry and the cake is formed. Washing: the cake is then washed, in single or multiple stages, using cake wash liquid to achieve the required cake purity.

The cake is dried under vacuum. Where lower residual moisture is required, our Moisture Reduction Systems (MRS Type 1 or Type 2) are applied to reduce moisture further.

Cake is discharged continuously and cleanly as the cloth turns away from the tray. Where the cake is persistent, a discharge blade can be provided.

Corrective measures maintain smooth cloth and belt movement throughout operation. Alarms are built in to flag plant-related issues and changes in parameters such as high vacuum or low compressed air.

Submergence and drum speed govern the balance between output and cake dryness. Higher submergence produces a thicker cake and greater throughput, but the shorter drying arc leaves higher residual moisture; reduced submergence lengthens drying time and lowers moisture, at the cost of production rate. We offer a range of submergence depths and select the right one for your duty, setting the form-time-to-dry-time balance through drum sizing, rotation speed and the timing of the valve bridge blocks. Vacuum level is chosen with equal care — higher vacuum builds cake faster, but compressible cakes can resist it, and premature dewatering ahead of a wash stage risks cake cracking.

We supply a variety of discharge types, selected according to how readily your cake releases from the medium. Scraper discharge, usually with air blowback, suits granular or crystalline solids and thicker cakes. Belt discharge handles media that blind rapidly and very thin cakes. Roll and string discharge suit thin or fibrous cakes. Precoat discharge — where an advancing doctor knife continuously shaves a thin layer from a bed of filter aid — is used for slimy, sticky or blinding solids, for very thin cakes and where exceptionally clear filtrate is required.

Steady, high-volume duties and slurries with variable cake thickness, moisture or stickiness — widely applied in chemicals, pharmaceuticals, minerals processing, food processing and sludge dewatering.

The separation point — the particle size with an equal probability of reporting to either stream, known as the d50 or cut point — is the central design target. It is set by cyclone diameter, vortex finder and apex sizing, cone angle and feed pressure. Smaller cyclone diameters generate greater centrifugal force and therefore finer separations. A larger vortex finder produces a coarser cut; a smaller one, a finer cut. The apex must be matched to the actual solids tonnage: undersized, it restricts underflow and risks roping or plugging; oversized, too much liquid reports to the underflow. As a broad guideline the apex diameter often falls around 0.1–0.2 times the cyclone diameter, but it is always chosen in combination with the vortex finder to achieve the required underflow density.

Inlet pressure directly governs the cut point, so stable pressure is essential to a consistent separation: below target pressure the cut coarsens, above it more fines are driven into the underflow. A sudden pressure change signals a change in feed rate — worth investigating, as it usually points to upstream pump trouble, an obstruction or wear. Usefully, once installed, most shifts in operating conditions can be accommodated simply by changing vortex finder and spigot diameters rather than replacing the unit.

Classification by particle size, de-sliming, desanding and thickening — continuous duty in a small footprint with no moving parts to wear or maintain. Selection is made from your feed volumetric flow rate, feed solids concentration, particle size distribution, required duty and target cut point.

Grit left in a process stream settles wherever velocity drops, abrading pumps, valves, agitators and filter media, and progressively occupying volume that should be available for treatment or reaction. Removing it early protects capital equipment from wear, preserves vessel and digester capacity, and improves the efficiency and service life of every separation stage that follows.

Installed ahead of pumps, filters and process machinery in mineral, chemical and effluent duties — anywhere abrasive solids threaten downstream equipment or where dense contaminants must be taken out of an otherwise usable stream.